How Mad Men solves the problem of finding the past

Tomorrow never knows. How Mad Men solves the problem of finding the past

It has been 17 months since the Season 4 finale of AMC's Mad Men, "Tomorrowland"--enough time that the show seems not just about another era but from another era. In October 2010, when Don Draper proposed to his secretary after a trip to Disneyland, Democrats controlled the House, Osama bin Laden was still alive, and ABC and NBC had yet to try their own early-'60s dramas, Pan Am (now on indefinite hiatus) and The Playboy Club (which has already bunny-hopped to that big grotto in the sky).

But Mad Men, which survived a rancorous contract negotiation between AMC and creator Matthew...